/Engine/Source/Runtime/GeometryCore/Public/DynamicMesh/MeshIndexUtil.h
For a given list/enumeration of Triangles, and an Overlay, find all the Elements in all the Triangles. Note that if ElementsOut is aTArray, it may include an Element multiple times.
namespace UE { namespace Geometry { template<typename OverlayType, typename EnumeratorType, typename OutputSetType> void UE::Geometry::TrianglesToOverlayElements ( const OverlayType * Overlay, EnumeratorType TriangleEnumeration, OutputSetType & ElementsOut ) } }